Go Direct^® Photogate (GDX-VPG)

Specifications and User Guide

Troubleshooting

General: Press the power button on the sensor to turn it on. Connect your sensor as described in the Getting Started instructions for your device.

• Primary Test: Is the unit powered on or connected to a USB power source?
• Secondary Test: Connect the Photogate to the data-collection program. Confirm that the Photogate has been identified by the program, and then use your hand to block and unblock the gate to confirm that the Photogate is working.

Additional Troubleshooting

• How do I set up a Go Direct Photogate to collect data using LabQuest App?
• How do I set up a Go Direct Photogate to collect data using Graphical Analysis or Graphical Analysis Pro?
• How do I set up Go Direct Photogate for data collection in a projectile motion experiment?
• How do you measure acceleration using Go Direct Photogates (GDX-VPG)?
• How can I use Go Direct Photogates (GDX-VPG) to time the Science Olympiad Scrambler event?
• How do I set up Graphical Analysis to use two Go Direct Photogates and only show time between gates?
• What is the timing precision of photogate measurements?
• Can I use a photogate to record animal movements?
• How can I use a photogate to count events?
• What nut size will work with the accessory rod that comes with photogates and force sensors?
• Why does my data table have holes (empty cells) in it?
• Can I use a photogate to measure the muzzle velocity from a gun or air cannon?
• How do I collect data using a Motion Encoder and a photogate simultaneously?
• Can you trigger a photogate with a green laser?
• Can I measure g with a photogate and Time of Flight Pad?
• Graphical Analysis photogate settings revert to Vernier Picket Fence settings, causing incorrect distance and velocity data.

WITH PICKET FENCE

Note: If the Photogate is not working with your Picket Fence, make sure that the protective plastic covering on the picket fence has been removed.

• How can I use a Vernier Photogate to measure g?
• How can I compare my g measurements to a local value and improve their accuracy?
• Why does my photogate record a really high velocity at the beginning of a trial with a picket fence?
• Why is my picket fence blue and black instead of clear and black?
• How do I measure motion with a photogate using the Vernier Cart Picket Fence?
• Does the Pasco picket fence work the same as the Vernier picket fence?
• What are the dimensions of the cart picket fence?
• Why does the Cart Picket Fence edge get detected by a photogate?

Specifications

• Infrared source: Peak at 880 nm
• Gate width: 77.5 mm
• Internal gate separation: 20 mm
• Distance from internal gates to bottom of photogate arms: ~10 mm
• Distance from internal gates to sides of photogate arms: ~5 mm
• Gate LED indicators: Off for unblocked gate; On for blocked gate
• Signal Output: Unblocked is high; Blocked is low
• Connections:
  ⚬ Wireless: Bluetooth^® v4.2 (wireless range 30 m unobstructed)
  ⚬ Wired: USB 2.0 full speed
• Battery: 650 mAh Li-Poly
  ⚬ Battery Life (single, full charge): ~10 hours continuous data collection
  ⚬ Battery Life (lifetime): 2 – 5 years (typical)

Calibration

Calibrate? No. This sensor cannot be calibrated.

Battery Troubleshooting

1. If the sensor can be turned on when connected by USB but not when disconnected from USB, the battery likely needs charging.
   ⚬ Charge the sensor for several hours and try again.
2. If the sensor shows fully charged but still won’t turn on when connected via USB, then the battery has likely disconnected.
   ⚬ Check the battery connection.
3. If the sensor still won’t turn on, try swapping the battery with a working sensor to see if the problem follows the battery or stays with the sensor.
   ⚬ If the problem stays with the sensor, the battery is probably not the issue.
   ⚬ If the problem follows the battery, the battery has likely reached its end of life.
4. If the battery is indeed at the end of its life, the sensor cannot be used even if connected by USB, so the battery will need to be replaced. Go Direct® 650 mAh Replacement Battery (GDX-BAT-650)
5. See How do I remove or replace a Go Direct battery? for more information (including a video).

Rechargeable batteries are covered by a one-year warranty.
Batteries should last two to five years in typical use.